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InGaAsP/InGaAs/InP single quantum well heterostructures after 20-keV phosphorus implantations performed with tilt angles set to 0 degree and 7 degree followed by rapid thermal annealing are studied. Photoluminescence and Raman studies reveal a significant improvement of the band-gap tuning process in the sample implanted at 0 degree.

Room temperature micro-Raman investigations of LO phonon and LO phonon-plasmon coupling is used to study the As outgassing mechanism and the disordering effects induced by ion implantation in Zn-doped GaAs with nominal doping level p=7 X 10(super 18) cm(super -3). Results make the Raman technique a simple and accurate technique to measure the range of defects induced by nuclear collisions during low-energy in implantation.

We report on the effects of the As/P intermixing induced by phosphorus ion implantation in InAs/InP quantum dashes (QDas) on their photoluminescence (PL) properties. For nonintermixed QDas, usual temperature-dependent PL properties characterized by a monotonic redshift in the emission band and a continual broadening of the PL linewidth as the temperature increases, are observed. For intermediate ion implantation doses, the inhomogeneous intermixing enhances the QDas size dispersion and the enlarged distribution of carrier confining potential depths strongly affects the temperature-dependent PL properties below 180 K. An important redshift in the PL emission band occurs between 10 and 180 K which is explained by a redistribution of carriers among the different intermixed QDas of the ensemble. For higher implantation doses, the homogeneous intermixing reduces the broadening of the localized QDas state distribution and the measured linewidth temperature behavior matches that of the nonintermixed QDas. An anomalous temperature-dependent emission energy behavior has been observed for extremely high implantation doses, which is interpreted by a possible QDas dissolution. [ABSTRACT FROM AUTHOR]

Low temperature photoluminescence (PL) measurements are carried out to investigate the influence of the high extent of intermixing induced by proton implantation and subsequent annealing on the optical and electronic properties of the InAs/GaAs quantum dots (QDs). Several QDs structures were proton implanted at various doses (5×1011–1×1015 ions cm-2) with an acceleration energy of 18 keV and then annealed at 700 °C for 30 s. A saturation of the emission energy blueshift is found to occur for implantation doses higher than 5×1013 ions cm-2 accompanied with a continual decrease in the intersublevel spacing energy suggesting that the intermixing process persists beyond the emission energy blueshift saturation. An additional emission peak was found to appear in PL spectra for proton doses higher than 1×1014 ions cm-2 and attributed to the coalescence of closely spaced QDs. Strain assisted predominant lateral intermixing is proposed as the main factor responsible for the observed behavior. [ABSTRACT FROM AUTHOR]

Several studies are conducted to explain the effects of the ion-implantation-induced band gap